package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Follow;
import com.hmdp.mapper.FollowMapper;
import com.hmdp.service.IFollowService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IUserService;
import com.hmdp.utils.UserHolder;
import org.springframework.beans.BeanUtils;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {
    @Resource
    private StringRedisTemplate stringRedisTemplate;
    @Resource
    private IUserService userService;

    @Override
    public Result follow(Long followUserId, Boolean isFollow) {
        //获取登录用户
        Long userId = UserHolder.getUser().getId();
        String key = "follows:"+userId;

        // TODO 关注功能
        //判断是否关注
        if (isFollow){
            //关注，新增
            Follow follow = new Follow();
            follow.setUserId(userId);
            follow.setFollowUserId(followUserId);
            boolean isSuccess = save(follow);
            //使用set集合的形式保存数据到redis
            if (isSuccess){

                stringRedisTemplate.opsForSet().add(key,followUserId.toString());
            }

        }
        else {
            //取消关注，删除
            boolean isSuccess = remove(new QueryWrapper<Follow>()
                    .eq("user_id", userId)
                    .eq("follow_user_id", followUserId)
            );
            if (isSuccess){
                stringRedisTemplate.opsForSet().remove(key,followUserId.toString());
            }
        }
        return Result.ok();
    }

    @Override
    public Result isfollow(Long followUserId) {
        //TODO 关注功能
        //查询是否关注
        Long userId = UserHolder.getUser().getId();
        Integer count = query().eq("user_id", userId).eq("follow_user_id", followUserId).count();
        return Result.ok(count>0);
    }

    @Override
    public Result followCommons(Long id) {
        //TODO 共同关注功能
        //当前用户的
        Long userId = UserHolder.getUser().getId();
        String key = "follows:"+userId;
        //目标用户的
        String key2 = "follows:"+id;
        Set<String> intersect = stringRedisTemplate.opsForSet().intersect(key, key2);
        if (intersect == null || intersect.isEmpty()){
            return Result.ok(Collections.emptyList());
        }
        //解析id集合
        List<Long> ids = intersect.stream().map(Long::valueOf).collect(Collectors.toList());
        List<Object> users = userService.listByIds(ids).stream().map(user -> BeanUtil.copyProperties(user, UserDTO.class)).collect(Collectors.toList());

        return Result.ok(users);
    }
}
